1. Field of the Invention
Embodiments of the present invention generally relate to the design and layout of a module used in a solar cell production line. Embodiments of the present invention also generally relate to an apparatus and processes that are useful for forming electrical connections in a solar cell device.
2. Description of the Related Art
Photovoltaic (PV) devices or solar cells are devices which convert sunlight into direct current (DC) electrical power. Typical thin film PV devices, or thin film solar cells, have one or more p-i-n junctions. Each p-i-n junction comprises a p-type layer, an intrinsic type layer, and an n-type layer. When the p-i-n junction of the solar cell is exposed to sunlight (consisting of energy from photons), the sunlight is converted to electricity through the PV effect. Solar cells may be tiled into larger solar arrays. The solar arrays are created by connecting a number of solar cells and joining them into panels with specific frames and connectors.
Typically, a thin film solar cell includes active regions, or photoelectric conversion units, and a transparent conductive oxide (TCO) film disposed as a front electrode and/or as a back electrode. The photoelectric conversion unit includes a p-type silicon layer, an n-type silicon layer, and an intrinsic type (i-type) silicon layer sandwiched between the p-type and n-type silicon layers. Several types of silicon films including microcrystalline silicon film (μc-Si), amorphous silicon film (a-Si), polycrystalline silicon film (poly-Si), and the like may be utilized to form the p-type, n-type, and/or i-type layers of the photoelectric conversion unit. The backside electrode may contain one or more conductive layers.
With traditional energy source prices on the rise, there is a need for a low cost way of producing electricity using a low cost solar cell device. Conventional solar cell manufacturing processes are highly labor intensive and have numerous interruptions that can affect production line throughput, solar cell cost, and device yield. Conventional solar cell fabrication processes include a number of manual operations that can cause the formed solar cell device properties to vary from one device to another. In typical solar cell electrical connection processes, formed electrical leads are manually positioned within a hosing that is manually bonded to the solar cell. These manual processes are labor intensive, time consuming, and costly. Additionally, as the size of solar cell substrates continues to increase, the floor spacing and number of technicians needed to perform these manual operations increases, resulting in significant overall costs of ownership. Moreover, as the solar cell sizes increase, manually making electrical connections in a central location becomes significantly more difficult. Therefore, a need exists for an automated electrical connection module in a solar cell fabrication system.